Ribbon-throw mechanism for type-writing machines.



I A. F. ENGBL. RIBBON THROW MECHANISM FOR TYPE WRITING MACHINES.

APPLICATION FILED APR.26, 1911.

1 20,404, Patented Mar. 19, 1912.

.hvenzor UNITED STATES PATENT OFFICE.

ARTHUR F. ENGEL, OF NEW YORK, N. Y., ASSIGNOR TO THE OLIVER 'I'YPEWRITER COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

RIBBON-THROW MECHANISM FOR TYPE-WRITING MACHINES.

Specification of Letters Patent.

Patented Mar. 19, 1912.

Application filed. April 25, 1911. Serial No. 623,294.

To all whom it may concern:

Be it known that I, ARTHUR F. ENGEL, a citizen of the United States, and a resident of New York city, in the county of New York and State of New York, have invented certain new and useful Improvements in Ribbon-Throw Mechanism for Type-Writing Machines; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

My invention relates to an improved typewriter ribbon throw device or ribbon vibrator, such as is usedin typewrit-ing machines, of the kind known as visible or sight writing machines, to carry the ribbon over the printing point for making the impressions and away from the printing point to expose to view the line of writing.

The object of my invention is to provide a typewriter ribbon vibrator that will con stantly shift the ribbon in a direction laterally of the same as it passes through the vibrating ribbon guides so that every part of the ribbon will be utilized in printing.

The invention consists in the novel construction and combination of parts hereinafter fully described and claimed.

In the accompanying drawings :-Figure 1 is a view in side elevation of the ribbon throw device embodying my invention. Fig. 2 is a top view of the device, on an enlarged scale. Fig. 3 is a sectional view of the parts on the line 33 of Fig. 2. Fig. 4 is a plan View of the ratchet-wheel, pawlmember and support therefor. Fig. 5 is a eross-section, taken on line 55 of Fig. 2. Fig. 6 is a cross-section, taken on line 6-6 of Fig. 2. Fig. 7 is a bottom view of the main ribbon and shifting ribbon-guide plates, together with the means for shifting the upper plate on the lower plate, taken on the section line 77 of Fig. 3.

An automatic typewriter ribbon vibrator made according to my invention comprises main parts, corresponding with those heretofore used for the ribbon vibrator of an Oliver typewriting machine, as follows, to wit, a main supporting arm 5, a horizontal base-plate 6 on the upper end of said arm, a horizontal, endwise vibrating, ribbon-guide plate 7, and three oscillating supporting links for said plate 7, two of which,

8, 8, are located intermediate the ends of the plate 7 and one, 9, of which is located at the forward end of said plate 7. The two links 8, 8, are pivoted at their lower ends to the base-plate 6 by means of a horizontal rockshaft 10 and at their upper ends to the plate 7 by means of pivots 11, 11. The forward link 9 is pivoted to the base-plate 6 by a horizontal pivot 12, and at its upper end to the plate 7 by a horizontal pivot 13. 'The rear links 8, S are aflixed at their lower ends to the rock-shaft 10, and said rock-shaft is adapted to turn in hearin s on the baseplate 6, and is provided with a crank-arm 14:, with the outer end of which is pivotally connected a pitman 15, through which vibratory motion is communicated to the said rock-shaft from one of the vibrating parts of the typewriting machine which is actuated when each of the key-levers thereof is depressed for printing a letter or character. Now referring to the parts more particularly relating to the present invention, 20 indicates a horizontally disposed plate which is mounted to slide endwise on the main ribbon guide-plate 7 and is provided with two rearwardly extending arms 21, 21 provided at their rear ends with ribbon guide loops 22, 22, through which the ribbon passes, and which are arranged at opposite sides of the printing point of the typewriter platen. The plate 20 is held in place and guided in its movement upon the plate 7 by means of two lateral lugs 23, 23, attached to the plate 20 and embracing the edges of the rear part of the plate 7 and by a headed stud 24: fixed in the forward part of the said plate 7 and engaging a longitudinal slot 25 formed in the forward part of the plate 20.

28 indicates a ratchet-wheel mounted on the plate 7 so as to turn on a vertical axis, and having its upper surface below and adjacent to the plate 20. In the particular form of construction illustrated, the said ratchet-wheel turns on an upright stud 29 secured to a cross-bar 30, that is attached at its ends to the arms 40, 40 of the plate 7, outside of the ratchet-wheel; said cross-bar being depressed at its central part, so as to support the said ratchet-wheel with its 'top surface flush with the top of the plate '7, which latter plate is cut away or provided with an opening between the inner ends of its arms 10, affording space for the ratchetwheel. The plate 20 is provided, above the ratchet-wheel, with a transverse slot 31, and the ratchet-wheel is provided with an upwardly extending crank-pin 32, which enters or engages said slot, these parts being so constructed and arranged that, as the ratchet-wheel is turned or revolved, the said crank-pin, operating in the slot 31, gives backward and forward movement to the said plate 20 on, or relatively to, the plate 7. The extent of movement or throw, given to the plate 20 by the ratchet wheel and its crankpin, is nearly equal to the width of the ribbon; the intent being that the ribbon shall be moved backward and forward, in each complete rotation of the ratchet-wheel, a distance suflicient to bring all parts of its width in position for the action of the type thereon. For giving such rotary motion to the ratchet-wheel a pawl member 35 is pivoted to the forward link 9, near the upper end or pivot 13 of said link, and is adapted to engage or act on said ratchet-wheel in a manner to turn the same a part of a rotation at each forward and backward movement of the device. The double pawl 35 is provided with two arms 36 and 37, which extend at opposite sides of the ratchet-wheel. One of said arms, 36, is provided with a tooth 38 having a forwardly facing shoulder or con tact face and is located at the side of the ratchet-wheel. at which the abrupt faces or holding shoulder of the ratchet-wheel face toward the rear, and said tooth 38 is adapted to engage one of the teeth of the ratchet Wheel and turn the same at each forward movement of the pawl. The arm 37 of the pawl member has at its rear end a shoulder adapted to act rearwardly on the ratchetteeth at the side of the ratchet-wheel at which the holding faces of the same face toward the rear. The two arms 36 and 37 of the pawl member are, moreover, joined by a spring or resilient connection adapted to hold or press both of said arms yieldingly against the teeth of the ratchet-wheel. Such sprin connection is formed, in the construction s own, by making the arm 37 of a strip of spring metal.

In the operation of the device described the pawl member is moved endwise, relatively to the plate 7 and the ratchet-wheel, through the oscillatory movement of the forward link 9 relatively to said plate 7, which occurs in each bodily movement or vibration of said plate 7. In the forward movement. of the pawl member, relatively to the ratchetwheel, the tooth 38 engages one of the teeth of the ratchet-wheel, and turns the wheel a distance equal to or somewhat more than the distance of one tooth; the arm 37 during such turning movement slipping over a tooth at the opposite side of the ratchet wheel. In the subsequent or backward stroke of the pawl member, the pawl arm 37 acts on one of the ratchet-teeth on the adjacent side of the ratchet-wheel to similarly turn the same; the tooth 38 at this time in its backward movement slipping over one of the teeth at the adjacent side of the wheel. The ratchet-wheel will therefore be turned an angular distance equal, at least, to the length of one tooth at each stroke or movement of the plate 7, forwardly and backwardly. It follows, from the construction described, that, as the ribbon is vibrated backwardly and forwardly to carry it over and away from the printing point, it will be given a lateral step-by-step movement, relatively to the printing point, first backwardly and then forwardly, as the crankpin 32, acting in the slot 31, moves forwardly or rearwardly in successive half rotations of the ratchet-wheel. As the ribbon is so laterally moved, the types act successively on different parts of the width of the ribbon, so that the entire width of the same is utilized.

It is to be understood that a device embodying the general features hereinbefore set forth may be variously modified in practice, and I do not, therefore, desire to be limited to the specific details of construction illustrated in the drawings and hereinbefore described, except so far as such details are claimed in the appended claims as parts of my invention.

I claim as my invention 1. A ribbon throw device embracing a base-plate, a main vibratory member, oscillating supporting links connected with said base-plate and with the main vibratory member, a shiftable member mounted on the main member provided with ribbon guides, and means affording a driving connection between the main member and the shiftable member operated through the vibratory movement of the supporting links relatively to the main member, and acting on the shiftable member to give forward and backward shifting movement to said shiftable member on the main member.

2. A ribbon throw device embracing a base plate, a main vibratory member, oscillating supporting links connected with said base-plate and with the main vibratory member, a shift-able member mounted on the main member provided with ribbon guides, a member rotatively mounted on said main member, a driving connection between said rotative member and the shiftable member, affording forward and backward shifting movement of the shiftable member on the main member, as said rotative member revolves, and means operated through the vibratory movement of the supporting links relatively to the main member for actuating said rotative member.

3. A ribbon throw device embracing a main vibrating member, a' shiftable member mounted on said main member and provided with ribbon guides, a ratchet wheel mounted on the main member, a driving connection between said ratchet wheel and the shiftable member, affording backward and forward shifting movement in the shiftable member as the ratchet wheel revolves, and a pawlmember actuated through the vibratory movement of the main member and provided with pawl arms that extend at opposite sides of the ratchet wheel and have yielding connections with each other; one of said arms having a holding tooth acting on the teeth of the ratchet wheel in the rearward movement of the pawl-member, and the other of said arms having a shoulder acting on said teeth in the forward movement of said pawl member.

at. A ribbon throw device embracing a base-plate, a main vibratory member, 0seillating supporting links connected with said base plate and with the main member, a shiftable member mounted on said main member, and provided with ribbon guides, a ratchet wheel mounted on the main member, driving means connecting said ratchet wheel and the shiftable member, giving shifting movement to said shiftable member during the vibratory movement of said main member both toward and from the printing point in the rotation of said ratchet wheel, and a pawl-member connected with one of said supporting links and acting on said ratchet wheel.

5. A ribbon throw device embracing a base-plate, a main vibratory member, 08- cillating supporting links connected with said base-plate and with the main vibratory member, a shiftable member mounted on the main member provided with ribbon guides and with a transverse slot, a ratchet wheel mounted on the main member and provided with a crank-pin engaged with said slot and a pawl-member connected with one 0 said links acting on said ratchet wheel to give forward and backward shifting movement to the shiftable member on the main member in the rotation of said ratchet wheel.

In testimony, that I, claim the foregoing as my invention I a'ltix my signature in the presence of two witnesses, this 13th day of April A. I). 1911.

ARTHUR F. ENGEL.

lVitnesses:

Cnnnmcs I. ENGEL, BERTIIA HmsoI-I.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

